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The Urey and Miller Story

When you tell stories in science and make it relevant to students they remember it better. Let’s take this example of the story of Urey and Miller and how their revolutionary experiments have impacted our ideas on the origin of life on Earth.

My Origin of Life on Earth story

So the first thing you should know is that the Earth is really old. Really really old. It’s 4.5 billion years old. But how old is that? I don’t know! So let’s do something else. If we imagine that the whole time that Earth has been around to be 24 hours. Then we can work with a timescale that we’re a little more familiar with. Ready to join me? Okay.

So at 0:00 the Earth just formed.

At 2:35 am prokaryotic life (bacteria + archaea) form

Nothing much else happens till 4pm. Bacteria are just hanging out there. Making the world oxic.

At 4pm eukaryotic life appears. These are organelle bound remember.

Again, nothing much happens until 9:45pm where insects appear.

10:33pm Dinosaurs appear

10:54pm Mammals appear

11:57pm Modern Homo sapiens appear

1 second ago – first Aboriginal cultures appear

All of recorded history lasts only 0.03 of a second.

Mind = blown. That’s pretty incredible isn’t it?

So then let me introduce you to two men: Oparin and Haldane. These guys both independently hypothesised the conditions of Early Earth. Haldane goes hmmm I wonder if biomolecules began to exist on Earth as a direct result of the conditions of Early Earth. And Oparin goes: oh man! I thought of it first, but I didn’t publish it in English and so no one knew about it! *sad face*

What did they think Early Earth was like?

it was HOT

it was gaseous

there was no oxygen

there was a lot of water

there was a lot of lightening storms

there was a lot of UV radiation as there was no atmosphere

Now introducing another two guys. Harold Urey and his slave graduate student Stanley Miller. Mr. Urey says “Hmmm I wonder if I set up an experiment with all those conditions, would it give rise to those biomolecules? If only I had a grad student to do all this research for me….Oh Stanley!!!!” And Stanley of course says “Yes Boss”.

If you’d like to see a set up of their experiment this site has a fantastic video to explain it.

In my powerpoint I have a whole series of other useful questions to ask of your students regarding the Nature of Science.